Nice deck, but you should note that you can't actually beat lionheart by deck-out unless I'm extremely unlucky or something. 3 times vs him and he just eternities/crusader eternity endowed he's scarabs back to the top of he's deck hence, he cant deck out.
He has a tendency to make everything immortal and then not be able to rewind anything.
He will sometimes stop quinting scarabs when he's low on cards if he doesn't already have a full quinted field before he hits <=5 cards remaining in order to bounce them. This appears to be a trick which was deliberately taught to him by Zanz, though I'm not 100% sure about that specific part of it.
However, he seems to eventually "forget" that he's not quinting things so as to survive deckout, and either plays a new creature (if he has one) and quints it, or just goes ahead and quints the scarabs he's been bouncing. Not really sure what the AI "thought" process is there, but often if you wait around long enough, you can still get the deckout even if he is bouncing with eternity. It can sometimes take several turns for him to "forget" and quint stuff.
It's certainly possible to lose to him if he gets into a scarab bouncing loop and doesn't "forget" and deck out soon enough, though.